To james alfred cooper



N5 Model.)

W. STELLNER'. MARINE SCREW PROPELLE R.

' Fla- 587,245, .ratent dhlyj2 7.1891

Fr es.

ATENT WILLIAM STELLNER, or MELBOURNE, VICTORIA, lissicnoaor ONE-HALF 1 ro JAMES ALFRED scores, or SAME PLACE. I

' MARINE SCREW-PROPELLEIR.

I SPECIFICATION forming part of Letters Patent No. 587,245, dated J uly 27. 1897.

' Applioation filedDeoember 23, 1898. seen No. 616,701. (No model.)

' ToaZZ whom it may concern. '1

'Bef-t known that I, WILLIAM STELLNER, engineer, a-snbject of the Queen of Great Britain and Ireland, residing at 277 Elizabeth 5' Street, Melbourne, inthe Colony of Victoria,

have invented a certain new and useful Improvement in Marine Screw-Propellers, of which the following is a specification ..1lie'object of my invention is to provide a propeller the blades of which are not only easily detachablefrom and adjustable on the arms which carry them, butby means of whicha greater speed is obtained. In the screw-propellers hitherto in use it has generally'been necessary when the pitch of the" blades required altering or a broken blade replacing to send down a diver or to clock the vessel; but with my invention the delay "and expense attendant on this operation is not, incurred, since if the after part of the. ship-.

be lightened it will rise sufiiciently to expose the blades above thewater, from which, one at a time, they can be approached by pu'nts or rafts for either replacement or adjustment. My invention, which is applicable to one, two, three, or four bladed screw-propellers, consists of blades which in contour resemble the segments of a circle and which are de tachable from arms protruding from the propeller-boss. In order to stiffen the said blades and also to ward off any ropes, chains, or other floating or falling obstructions which might cross the propellers pathway, there are placed between the lcadin g ends of each blade connectingstays. Au unbroken circle is thereby formed on the leading side of the propeller, the blades of which are adjustable in three ways-radially from the boss, longitudinally on the arms, and also as regards their pitch. The radial and longitudinal adjustment is effected by cross-shaped holes in the blades, while the pitch is varied by a pitchadjusting wedge (also having cross-shaped holes) situated between the blades and the rms. The bolts or rivets passing through these holes are locked in any required position by a chock or checks out to fit into the holes; but in order'that my invention may be better understood I will now refer to the 5o accompanying sheet of drawings, which are the several views.

to be take'nas part of this specification and read herewith.

Figure 1 represents an elevation of a four bladed screw looked at from the aft or driving side. Fig. 2 represents-a side elevation of the same, showing the connecting-stays, which, as will be seen, are attached to the back of the leading ends of the blades. Fig.

3 represents an elevation of the screw, looked at fr'om the forward or leading side. Fig. 4 represents, on an enlarged scale, a view of ..one-of the blades looked at-from its driving side. Fig. 5showsa sectionalplan of a blade between which and thearm-is tl1e pitch-ad- 'justing wedge. Fig. 6 represents a front, view of the wedge. Fig. 7 represents a per spectiv-eview of the checks which are placed in the elongated holes shown in Fig. 5. Similar letters of reference indicate similar .or corresponding parts where they-occur in 7 On reference to the drawingsit will be seen that A is the boss, to which are integrally at tached the arms B. The fore and aft edges f of lhese'arms, as shown'iu =l ig. 2, are not square with the axis of the boss, but trail aft at the outside end. The sides of the arms "may be at any angle with the aforesaid axis, which angle is governed by the pitch. At the end' of the arms areconnected the blades C, each one of which in contour is a perfect segment of a circle. These are preferably secured by bolts which pass through .the recessed cross-shaped holes D5 Attached to the leading ends of the blades, by bolts, rivets, or other means, are the rectangular sectioned connecting stays] H. These extend from blade to'blade, and at both ends, in order not to reduce the area of the or backof the said blades.

- The longitudinal and radial adjustment of the blades is effected by the cross-shaped holes D. These permit them tobe moved either fore or aft and either from or to the boss. \Vhen the desired position is ascei tained, the shape around the bolt or rivet E is filled by the shocks, such as F, which effectuall y lock both bolt and blade. The-heads of the said bolts or rivet-s, by the recessed. 10o

driving side, are secured to the trailing face 9'0 used.

I do not bind. myself to a wedge of the particnlar inclination shown, nor to the shape of the holes within it, since these particulars will all vary with the different conditions under which each particular is constructed. The blades, wh eh can be attached to existing propellers, may also be either curved or flat, the amount of the curvature depending upon the diameter and the pitch.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In marine screw-propellers, the combination of the blades and arms, with pitchadjusting wedges interposed bet-ween 'the blades and arms, substantially as and for the purpose described.

2. In marine screw-propellers, the combination of the arms, with blades 0 each forming a. complete segment of a circle detachably secured to and adjustable on the arms, substantially as and for the purpose described.

the blades and arms, and securing-bolts, all

substantially as and for the purpose described.

5. Inmarine screw-propellers the combination of a boss A having integral arms B to which are detachably connected blades (3 having recessed cr0ss-shaped holes D; with pitch-adjusting wedges Ginterposed between said blades and arms, all substantially as and for the purpose described.

6. In marine screw-propellers the combination of a boss A having integral arms B to which are detachably connected blades 0 having recessed cross-shaped holes I); with pitch-adjusting wedges Ginterposed between said blades and arms; and stays H connecting and stiifening the blades, all substantially as and for the purpose described;

In witness whereof I have hereunto set my hand in presence of two witnesses.

-\VILLIAM S ELLN ER.

Witnesses EDWIN PHILLIPS,

CECIL Woons LE ILAsrRIER. 

